Assessments of children's behavior problems, competencies and cognitive functioning are being obtained on normal controls and children with thyroid and sex hormone abnormalities in order to determine whether hormone levels affect patterns of cognitive abilities and behavioral adaptation. The study also tests the hypothesis that increases in particular hormone levels affects patterns of cognitive functioning by improving automatization abilities at the expense of ability to engage in complex perceptual restructuring. It is also designed to determine whether premature craniosynostonis noted in hyperthyroid children interferes with cognitive functioning. In general, our preliminary analysis shows that girls more than boys exhibit problems of management if they have an endocrine abnormality. This finding suggests a brain and behavior relationship which needs to be investigated further.